"""用量查询 — Tavily 剩余额度 + 百度 VDB 免费额度"""

import time
import hmac
import hashlib
import datetime
import requests


def check_tavily_usage(api_key: str) -> dict:
    if not api_key:
        return {'error': '未配置 API Key', 'available': False}

    try:
        resp = requests.get(
            'https://api.tavily.com/usage',
            headers={'Authorization': f'Bearer {api_key}'},
            timeout=10,
        )
        if resp.status_code == 429:
            return {'error': '查询过于频繁（10分钟内限10次）', 'available': False}
        if resp.status_code != 200:
            return {'error': f'API 返回 {resp.status_code}', 'available': False}

        data = resp.json()
        key_data = data.get('key', {})
        acct = data.get('account', {})

        usage = key_data.get('usage', 0) or 0
        limit = key_data.get('limit', 0) or 0
        remaining = max(limit - usage, 0) if limit else 0

        return {
            'available': True,
            'key': {'usage': usage, 'limit': limit, 'remaining': remaining},
            'account': {
                'plan_limit': acct.get('plan_limit', 0) or 0,
                'search_usage': acct.get('search_usage', 0) or 0,
                'paygo_usage': acct.get('paygo_usage', 0) or 0,
            },
        }
    except requests.exceptions.Timeout:
        return {'error': '请求超时', 'available': False}
    except requests.exceptions.RequestException as e:
        return {'error': f'网络错误: {e}', 'available': False}


def _bce_sign(access_key: str, secret_key: str, method: str, path: str,
              headers: dict, params: dict = None) -> str:
    timestamp = datetime.datetime.utcnow().strftime('%Y-%m-%dT%H:%M:%SZ')
    expiration = 1800

    auth_string = f'bce-auth-v1/{access_key}/{timestamp}/{expiration}'
    signing_key = hmac.new(
        secret_key.encode('utf-8'),
        auth_string.encode('utf-8'),
        hashlib.sha256,
    ).hexdigest()

    signed_headers = sorted(headers.keys(), key=lambda k: k.lower())
    canonical_headers = ''.join(
        f'{k.lower()}:{headers[k].strip()}\n' for k in signed_headers
    )
    canonical_uri = path

    if params:
        canonical_query = '&'.join(
            f'{k}={v}' for k, v in sorted(params.items())
        )
    else:
        canonical_query = ''

    canonical_request = f'{method}\n{canonical_uri}\n{canonical_query}\n{canonical_headers}'

    signature = hmac.new(
        signing_key.encode('utf-8'),
        canonical_request.encode('utf-8'),
        hashlib.sha256,
    ).hexdigest()

    return (f'bce-auth-v1/{access_key}/{timestamp}/{expiration}/'
            f'{";".join(k.lower() for k in signed_headers)}/{signature}')


def check_baidu_vdb_quota(access_key: str, secret_key: str) -> dict:
    if not access_key or not secret_key:
        return {'error': '未配置 VDB Access Key / Secret Key', 'available': False}

    host = 'vdb.bj.baidubce.com'
    path = '/v1/vdb/instance/freeQuota'
    method = 'GET'

    headers = {
        'host': host,
    }
    auth = _bce_sign(access_key, secret_key, method, path, headers)
    headers['Authorization'] = auth
    headers['Content-Type'] = 'application/json'

    try:
        resp = requests.get(
            f'https://{host}{path}',
            headers=headers,
            timeout=10,
        )
        if resp.status_code != 200:
            return {'error': f'API 返回 {resp.status_code}', 'available': False}

        data = resp.json()
        free_quota = data.get('freeQuota', 0)
        return {
            'available': True,
            'freeQuota': free_quota,
        }
    except requests.exceptions.Timeout:
        return {'error': '请求超时', 'available': False}
    except requests.exceptions.RequestException as e:
        return {'error': f'网络错误: {e}', 'available': False}